package Java8;

import java.util.Arrays;
import java.util.List;
import java.util.function.Predicate;

public class FunctionTest {

  public static void main(String[] args) {
    List<Integer> list = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9);

    // Predicate<Integer> predicate = n -> true
    // n is passed as parameter to test method of Predicate interface
    // test method will always return true no matter what value n has.

    System.out.println("Print all numbers:");

    //pass n as parameter
    eval(list, n -> true);

    // Predicate<Integer> predicate1 = n -> n%2 == 0
    // n is passed as parameter to test method of Predicate interface
    // test method will return true if n%2 comes to be zero

    System.out.println("Print even numbers:");
    eval(list, n -> n % 2 == 0);

    // Predicate<Integer> predicate2 = n -> n > 3
    // n is passed as parameter to test method of Predicate interface
    // test method will return true if n is greater than 3.

    System.out.println("Print numbers greater than 3:");
    eval(list, n -> n > 3);
  }

  public static void eval(List<Integer> list, Predicate<Integer> predicate) {

    for (Integer n : list) {

      if (predicate.test(n)) {
        System.out.println(n + " ");
      }
    }
  }
}
